Is it better to rebuild a 904 or buy a aftermarkt unit??

I am in the process of building my 70 dart swinger. Car has a 8.75 rear with 3:55 gears. I am sticking with the factory 318 that i estimate max 400hp when completed, probley more like 350hp with my first time port work. But anyways I had planned on having my stock 904 rebuilt. I rebuilt a 904 in high school years ago with help but dont feel confident doing one on my own. But now i have happened to stumble across the TCI sizzler(rated for 300hp)for $765 the TCI streetfighter(rated for 450hp) for arond $1100 and the Performance Automatic(rated for 400hp)for around $1100 but comes with a forever warranty.

I would still have to pay for shipping on all three transmisssions and also buy a torque converter. So the question is with these options out there would someone in my shoes be better off having a shop rebuild my stock trans or buy an aftermarket trans?

I have no clue what the average shop charges but it seems like the aftermarket transmission are pretty cheap. Then comes the problem of finding a trans shop that has a good reputation.

Any suggestions?? Just curious if anyone has used the TCI transmissions or the Performance Automatic transmission and the average price differance from paying a local shop.

Thanks for any input
Mark